Railway track brake



June,3;(),""1 93 1. w. BXsELER RAILWAY TRACK BRAKE Original Filed Feb. '5, 1926 2 Sheets-Sheet 1 Jwm/m w. BAsELER RAILWAY TRACK BRAKE June 30, 1931.

Original Fil ed Feb. 5, 1926 2 Sheets-Sheet 2 1/71 67? for: Wolfyarry Bis e/er I Patented June 30, 1931 'WOLFGAING' nzi'snrnn, or MUNICH, GERMANY RAILWAYTRACK BRAKE 1 Application filedFebruary 5,:1926, Serial ,No. 86,222, and in Germany February 9, 1925. Renewed V I i M y 19,1930.) J 1 I J My inventionv relates to railway track brakes more especially of the stationary kind operated by electromagnetic meansl .Its primary objects areto provide eificient'means 5 for stopping cars and to improve and perfect Itationary carbrakes as hereinafter more fully describedf f The railway track brakes serving to, brake the wheels of; railway cars bymagnetic ac tion as hitherto designed either'havetoo 10w abraking power or do'not allowa nice ad- 'ustment ofjrthe braking force. The track rake'acording to the present invention is so designed asto obviate these drawbacks. r i According to my experience,liigh braking effects can be obtained only if a high magnetic flux is forced across the rim of the wheel to be braked, such. manner that on the one side'of the "rim is'formedthe north pole,

- on the other side the south pole of the mag net, means being provided to allow the. magnetlc flux to ;close[underneath' the "rails, I

have found, that the brakingeifect :can

considerably increased by using, pole, shoes composed of a plurality of laminae extending in the longitudinal direction. As a rule the braking effect of brakesoperated.lOy eddy current first rises with, increasing :velocity I 1 to a, maximum value toi'slowlyjdrop. there after until atjinfinitelyhighwelocity of the wheel the zero point is reached. "Thevvelocity V at which thejmaximiim braking effect is ob? tainedis called critical velocity. The move mentpo'fithe wheelrimsrelative to thepole shoes (braking, bars) is composed. of two parts,tviz. rotation about the wheel axis and translation movement of the car; The-'ro-l tary movement, generates eddy currents in r 1 the wheel rims, the translation. movement in the pole shoes. In view of this fact/it would seem advisable to uselsolidp'ole shoesin order:

to obtainga maximum of eddy, currents in these shoes and in consequence thereofthe I highest possible brakingeflecfl I h'ave now found that this assumption is not correct.

If solid ;brakingrbars are used, the critical velocity is diminished to such an extent that the total braking efi'ect is comparativelylow.

In contradistinction thereto, the use of lamii 5 nated pole shoes (braking bars) has proved parallel :to

the simplest form,

to result in a great increase of thetotalbraking efl'ect'within the range ofvelo'cities aris ing in the switching of cars; Apart fronil this construction of the pole shoes or braklow the widest wheel rimsto pass through'gf between them. In consequence of such ar rangement a comparatively large airgap forms between the wheel rim and themagnet poles, which prevents the formation ofa suf-' i ciently high magnetic flux and causes the g Wheels to always applythemselves only to one shoe ofapairfof pole shoes, thereby tre-,

quently causing aderailment,

It has already been suggestedto arrange the pole shoeson arms adapted-to. rock about a a common hinge pin so that on themagnet bleing energiz ed thefarms carrying thepole shoes will describe a circleabout the hinge pin and W111 apply themselves against the car wheels. ;;Howe'v er this arrangementdoes V notallow the pole shoes, or braking rails to of the wheels :pas si ngthrough between them.

fully apply their brakingsurface tothe rims In contradistin'ction thereto -I arrange ,the

pole-shoes or braking barsilin such manner that'they can move towardsjand away from each other with their: brakingsurfaces in be brakedfl I 4 I further 'vprefer providing additional means, besides the'magnetic ones, for moving the braking bars. In the drawings'afli xed to bodying my invention are illustrated dia this specification and formlng part thereof several modifica ti'ons of an electromagnetic track brake em-i i each other and to the wheels to I gramatically by way of example, the

drawlngs 4 I p 1 a Fig. 1 is an elevation, partly in section, of; Figs. 2i's. a similar view of a brake which: thefllegs ofithemagnet and the shoes are hinged tothelegs; 1

re hinged to the. base I Fig. Sis a similar view of a brake'in which legs of the magnet are laminated and-Lear v pable of resilient deformation." 7

Fig. 4; is a front elevation of a brake which is composed throughout of laminae capable of relative displacement.

Fig. 5 is an elevation partly in section of the top part of a brake comprising movable pole shoes and hydraulic or pneumatic means for acting on these shoes in the direction of application.

Fig. 6 isa perspective view of a braking structure using magnets and pole shoes or braking bars with the addition of'hydraulic cylinders and pistons.

Referring first to Fig. l, 1 is one of the tracir rails, 2 is the lower part of a car wheel resting on rail 1. 8, 3 are the vertical legs ofa horseshoe magnet, l, 4 are the electric windings surrounding these legs and 5, 5 are the pole shoes mounted on the legs 3 in such manner as to be capable of freely moving towards each other and towards the wheels which passes between them.

The magnets formed by the legs 3 and the windings t are strong enough to cause the entire magnetic-flux to be closed underneath the rail 1. Theformation of an air gap between the brake and the rim of wheel 2 is avoided by the brake shoes Bbeing capable of moving bodily on the legs of the magnet in the direction towards the wheel so as to closely apply themselves against the wheel'rim.

In the device illustrated in Fig. 2, the pole shoes 5, instead of being freely movable on the legs of the elect-romagnet, are hinged to the legs 6, these latter being hinged in turn tothe base portion of themagnet so as to-be able to rockon this base portion andthereby to allow the operative faces of the pole shoes to fully apply themselves against the rim of the wheel 2.

In the modification illustrated in Fig. 3 the pole shoes 5 are mounted on the upper ends of bundles of thin resilient laminae 7 forming the legs of the magnet, which are thus rendered resilient in such manner as to allow the pole shoes 5 to move in the direction towards each other and towards the rim of thewheel 2.

In the brake illustrated in Fig. 4c the legs 8 of the magnet as well as its base piece 9 and the pole shoes 10 themselves are composed of laminae capable of moving relatively to each other so as to allow the operative faces of the pole shoes 10 to apply themselves against the wheel 2., In a brake designed as shown in Fig. &, the injurious influence of eddy currents is avoided also.

If it is desired to further increase the braking action,'for instance ifit is desired to brake entire trains, pistons 11, movable in hydraulic cylinders and actingon the pole shoes 5 or 10 can be provided,these pistons acting towardsforcing the pole shoes against the wheels with an additional force which together with the magnetic flux causes :the

wheels to be reliably braked without allowing them to rise.

The braking device illustrated in Fig. 6 shows the general design of magnets and pole shoes or braking bars as disclosed in Fig. 4i with the addition of hydraulic cylinders and pistons as shown in Fig. 5.

I wish it to be understood that I do not desire to be limited to the exact details of construction shown and described for obvious modifications will occur to a person skilled in the art.

I claim 1. A railway brake comprising a U-shaped electromagnet located in the trackway with its legs on opposite sides of a rail, and pole shoes mounted on the upper ends of said legs to slide horizontally toward and away from each other and to engage the opposite sides of a wheel on said rail when the magnet is energized.

2. A railway brake comprising a U-shaped electromagnet located in the trackway with its legs on opposite sides of a rail, and pole shoes mounted on the upper ends of said legs to slide horizontally toward and away from each other and to engagetheopposite sides of a wheel on said rail whenthe magnet is energized said pole shoes being formed at least in part of laminations which are parallel to the rail. g

'3. A railway brake comprising a U-shaped electromagnet located in the trackway with its legs on opposite sides of a rail, and pole shoes mounted on the upper ends of said'legs to slide horizontally toward and away from each other to engage the opposite sides of a wheel on said rail when the magnet is energized, each pole piece being inclined upwardly from its associated magnet leg towagdtheposition occupied by a wheel on the rai 4:; A railway brake comprising a U- shaped electromagnet located in the trackway with its legs on opposite sides of a rail, and pole shoes mounted on the upper ends of said legs to slide horizontally toward and away from each other to engage the opposite sides of a. wheel on said rail when themagnet is energized, each pole piece being formed at least in part oflaminations which are parallel to the rail and are inclined upwardlyfrom the associated magnet leg toward theposition occupiedby a wheel on the rail.

5. A railway brake comprising a U- shaped electromagnet located in the trackway with its legs on opposite sides of a rail, and pole shoes associated with the upper ends of said legs and formed at least'inpart of laminations which are parallel'to the rail. 7 In testimony whereof I aflix my signature.

WOLFGANG BASELER. 

